分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:In the littlest Higgs model with T-parity (LHT) the newly introduced mirror quarks have flavor-changing couplings with the Standard Model (SM) quarks and may enhance the flavor-changing neutral-current (FCNC) top quark interactions which are extremely sup
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:In the minimal supersymmetric standard model the R-parity violating interactions can trigger various exotic three-body decays for the top quark, which may be accessible at the LHC. In this work we examine the R-violating decays t-> c X_1 X_2, which includ
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:As discussed recently by Hooper and Tait, the singlino-like dark matter in the Minimal Supersymmetric Standard Model (MSSM) extended by a singlet Higgs superfield can give a perfect explanation for both the relic density and the Pamela result through the
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:The left-right twin Higgs model predicts a light stable scalar \hat{S}, which is a candidate for WIMP dark matter. We study its scattering on nucleon and find that the cross section is below the CDMS II upper bound but can reach the SuperCDMS sensitivity.
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:We briefly review the supersymetric explanation for the cosmic dark matter. Although the neutralino in the minimal supersymmetric model (MSSM), the next-to-minimal supersymmetric model (NMSSM) and the nearly minimal supersymmetric model (nMSSM) can natura
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:Assuming the lightest neutralino solely composes the cosmic dark matter, we examine the constraints of the CDMS-II and XENON100 dark matter direct searches on the parameter space of the MSSM Higgs sector. We find that the current CDMS-II/XENON100 limits c
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:Extensions of the Standard Model often predict new chiral interactions for top quark, which will contribute to top quark spin correlation and polarization in tt?tt?t\bar{t} production at the LHC. In this work, under the constraints from the current Tevatr
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:The anomaly of the top quark forward-backward asymmetry AtFBAFBtA^t_{FB} observed at the Tevatron can be explained by the t-channel exchange of a neutral gauge boson (Z') which has sizable flavor changing coupling for top and up quarks. This gauge boson c
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:In this talk we briefly review the current CDMS/XENON constraints on the neutralino dark matter in three popular supersymmetric models: the minimal (MSSM), the next-to-minimal (NMSSM) and the nearly minimal (nMSSM). The constraints from the dark matter re
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:For the experimental search of neutralino dark matter, it is important to know its allowed mass and scattering cross section with the nucleon. In order to figure out how light a neutralino dark matter can be predicted in low energy supersymmetry, we scan
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:Little Higgs theory naturally predicts a light Higgs boson whose most important discovery channel at the LHC is the di-photon signal pp→h→γγpp→h→γγpp\to h\to \gamma\gamma. In this work we perform a comparative study for this signal in some typical little
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:As a top quark factory, the LHC can test the new physics models used to explain the top quark forward-backward asymmetry A^t_FB measured at the Tevatron. In this work we perform a comparative study for two such models: the W'-model and the color triplet d
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:In order to explain the Tevatron anomaly of the top quark forward-backward asymmetry AtFBAFBtA_{FB}^t in the left-right twin Higgs model, we choose to give up the lightest neutral particle of h^h^\hat{h} field as a stable dark matter candidate. Then a new
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:We examine the parameter space of the constrained MSSM by considering various experimental constraints. For the dark matter sector, we require the neutralino dark matter to account for the relic density measured by the WMAP and satisfy the XENON limits on
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:Motivated by the recent LHC hints of a Higgs boson around 125 GeV, we assume a SM-like Higgs with the mass 123-127 GeV and study its implication in low energy SUSY by comparing the MSSM and NMSSM. We consider various experimental constraints at 2-sigma le
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:Due to the limited statistics so far accumulated in the Higgs boson search at the LHC, the Higgs boson property has not yet been tightly constrained and it is still allowed for the Higgs boson to decay invisibly to dark matter with a sizable branching rat
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:In a topcolor-assisted technicolor model (TC2) with large FCNC top quark couplings, we study its correlated contributions to the top quark forward-backward asymmetry (AF B ) at the Tevatron, the top charge asymmetry (AC) and the triple-top production at the LHC. Under current constraints on the top quark from the LHC and Tevatron (such as the total and differential production rates), we scan the parameter space of such a TC2 model. We find that in the allowed parameter space the TC2 model can explain the Tevatron measured AFB at 2σ level, but meanwhile significantly enhance AC at the LHC. Such enhanced AC, albeit currently allowed by the LHC measurement at 2σ level, will serve as a test of TC2 with the improvement of measurement precision at the LHC. Then with all the constraints (including the requirement to explain AF B at 2σ level and satisfying the current LHC measurement of AC at 2σ level), we find that the TC2 model can induce sizable triple-top production at the 14 TeV LHC (the production rate can maximally reach 16 pb). Due to the low SM backgrounds, the triple-top production can also be a good probe for TC2 model, complementary to AC.
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:We consider the natural supersymmetry scenario in the framework of the R-parity conserving minimal supersymmetric standard model (called natural MSSM) and examine the observability of stop pair production at the LHC. We first scan the parameters of this s
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:Confronted with the LHC data of a Higgs boson around 125 GeV, different models of low energy SUSY show different behaviors: some are favored, some are marginally survived and some are strongly disfavored or excluded. In this note we update our previous sc
分类: 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要:Inspired by the recent LHC Higgs data and null search results of supersymmetry (SUSY), we scan the parameter space of the Minimal Supersymmetric Standard Model (MSSM) with relatively heavy sparticles (1-3 TeV). Then in the parameter space allowed by curre